Art of centrifugal separation.



H.- DE RAASLOPP & T. B. BROWN. ART 0? GENTRIFUGAL SEPARATION.

APPLICATION FILED JULY-31, 1911. 1,050,622. Patented Jan.14,-1913.

4 SHEETSSHBET l.

o WITNESSES:

Q [I V/ A g M/ MM M W ATTORNEY H. DE RAASLOPP & T. E. BROWN. ART OFGENTRIFUGAL SEPARATION.

APPLIOATION FILED JULY 31, 1911.

1,050,622; 1 1 PatentedJan.14,l913.

4 SHEETS-SHEET 2.

H. DE RAASLOFP & T. E. BROWN. ART OF OENTRIFUGAL SEPARATION.

APPLICATION FILED JULY 31, 1911. 1,050,622. Patented Jan. 14,1913.

4 SHEETS-SHEET 3.

H. DYE RAASLOFF & T. E. BROWNJ 4 ART OF CENTRIFUGAL SEPARATION.APPLICATION FILED JULY 31, 1911.

1,050,622, Patented Jan. 14,1913.

4 SHEETS-SHEET 4.

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UNITED STATES PATENT OFFICE.

HARALD DE RAASLOFF AND THOMAS E. BROWN, 01 NEW YORK, N. vY.

ART OF CENTRIFUGAL SEPARATION.

Specification of Letters Patent.

Patented Jan. 14., 1913.

Application filed July 31, 1911. Serial at. 841,419.

.Art of Centrifugal Separation, of which the following is aspecification.

This invention relates to improvements in centrifugal separators.

The invention particularly relates to machines for the separation ofliquids from solids, and the separation of liquids of different specificgravities from each other.

The present application relates particularly to improvements incentrifugal ma-' chines for operating'our improved'process of filtrationby the aid of centrifugal force; an important element in the saidprocess being the utilization of an overbalancing atmospheric pressure,in opposition to the centrifugal force, for the purpose of preventingthe egress of the lighter liquid from the separating chamber along withthe heavier concentrated materials.

The present application relates to centrifugal machines for effectingthe continuous separation of liquid and solid matters, and it especiallyrelates to centrifugal machines in which the centrifugal force issupplemented by filtering means to enable'the liquid to be freed fromsolid matters too fine to be separated by centrifugal force alone, andsaid filtering means are so constructed and arranged that the ,flow ofthe liquid therethrough is opposed to the centrifugal force, so that thecentrifugal force tends to remove the solid particles from the surfacesof said filterlng means and to keep them clean and in good operativecondition.

Other important features of the present application are the means forcausing overbalancing atmospheric pressure, the means for dryingthe'concentrates, and the means for clarifying the separated liquid.

Still other important features and parts of the invention, will beapparent from the description and the claims hereinafter following.

The invention to which this application relates is applicable tovariousmodifications of centrifugal machines, and the accompanyingdrawings illustrate four forms. of

such machines embodying said invention. But said invention is notrestricted to such modifications, but can be applied to all centrifugalmachines in which the separation is effected in separating vesselsprovided with external outlets for the. concentrates led to a pointnearer the axis of rotation than .is the. extremity of said vessels, theterm extremity indicating the part of the vessel radially farthest fromthe axis of rotation. The invention is also applicable to all.centrifugal machines in which an overbalancing atmospheric pressure isutilized to prevent the egress of the lighter liquid along with theconcentrates.

As hereinbefore stated, the present invention relates particularly to.improvements in machines for applying the process set forth in ourapplication for United States Letters Patent, filed June 30th, 1910.Serial Number 569,631, wherein the principle of the vacuum and itsutility in preventing the discharge of the lighter liquid along with theconcentrates, so that continuous separation of the liquid from theconcentrates can be. commercially effected, is fully set forth anddisclosed. In the present application therefore, the specification ischiefly concerned with the improvements in the machine and the processis only briefly referred to.

Referring to the said drawings which accompany the specification, to aidthe description, Figure 1 is a broken vertical section and elevation ofone form of machine embodying our invention, and Fig.2 is a plan andhorizontal section of the same machine, the plane of the sectional partsof Fig. '2, being on the line 2-2 of Fig. 1. Fig. 3 is an edge elevationof the plows or scrapers for acting on the concentrates, the brush forcleaning a filter, and certain connected parts. Fig. 4 is a brokenvertical section and elevation on large scale, of certain parts shown inFig. 1. Fig. 5 is a broken vertical section and elevation on large scaleof amodification of the machine, wherein the material is drawn in frombelow. ,Fig. 6 is a broken vertical section and elevation, on largescale, of another modification combining certain features of' themachines illustrated in Fig. 1 and in Fig.

5. Fig. 7 is a broken sectional detail of certain parts of anothermodification of the machine, wherein the valve which determines theatmospheric line is controlled by a float.

Referring to Figs. 1, 2, 3 and 4, 1 1s the axis of revolution preferablyin the form of a pipe, closed near the bottom 2, and revolved insuitable bearings 3-4 at high velocity by any suitable means, as pulley8. The materials to be separated, as liquids and solids, are deliveredinto a funnel 6, fixed on the upper end of pipe 1. Said pipe 1.communicates with separating chamber 10, which is shown as of annularshape concentric to pipe 1, (Fig. 2), by branch pipes 11 and open traps9. Said chamber 10 is preferably divided into an inner and an outerportion by a filter 15, situated between the inlet and the liquid outletof chamber 10, the flow through the filter being in a direction opposedto the centrifugal force. The

outer part of said chamber 10 is contracted to form an annulus 12 ofsmall cross sectional area. The filter 15 may be made in any suitablemanner, and of suitable filtering material for the particular substancesto be treated. The concentration of the heavier materials takes place inthe outer end of said separating chamber 10. Said chamber 10 is of suchdimension radially to the machine that the extremity of said chamber isoutside of, or farther from the axis of rotation than, the line ofatmospheric pressure a-a. Said line of atmospheric pressure indicatesthe line on which, when the machine is revolving at its predeterminedvelocity, the pressure is equal to atmospheric pressure. The position ofthe said line of atmospheric pressure may be thus explained: Supposesaid chamber 10 to be tightly closed, except at the annular outlet 18,and to be full of liquid. Now, if the said chamber 10'be rapidlyrevolved the liquid in said chamber will move outwardly and the liquidin said annular outlet will move upwardly and inwardly under theinfluence of the centrifugal force generated by the revolution of saidchamber 10. The surface of the liquid in said outlet 18 will now form aparabolic wall, at the line a-a, which, when the apparatus is revolvingat such designed high speed that the force of gravity may be neglected,will be practically the wall of a cylinder concentric with the axis ofrevolution of said chamber 10. We call the position of this wall theline of atmospheric pressure, because, at the position of said wall, thepressure of the liquid is equal to atmospheric pressure. The liquid insaid chamber 10 will, at the same time, have moved outwardly from theaxis of the said vessel, so that there will be a vacuum near the centerof said vessel, and the surface of the liquid therein will form a wallat the position of the line 2z, which will also be practically the wallof a cylinder concentric with the axis of revolution of said chamber 10.We call the position of said last named wall the line of zero pressure,because at the said Wall the pressure prevent the admission of air), andtoward the axis of rotation; and the annular passage formed by saidcasing 14 may be considered as an extension of said chamber 10,continued externally to said chamber 10 and inwardly toward the axis ofrotation. Of course said chamber 10 might be without the contractedannular opening, or might have a long annulus of tubular like section,or might be formed of various shapes, but in all cases we consider theextremity of said chamber to be the part thereof, farthest from the axisof rotation, and practically where the connection with casing 14 ismade. Said casing 14 contains plows or scrapers 16, carried on the arms17, which are driven at proper speed in any suitable manner, as

by differential gearing 2l-22, or any suit- 5 which they may be removedby another plow or scraper 24, or in any suitable manner. The preferredshape and construction of said plows or scrapers 16 is shown in Fig. 3.It is to be understood that any other suitable form of conveyer orscraper and casing may be employed instead of the plow and casing shownin the accompanying drawings and described in the specification. Saidseparating chamber 10 is closed at its inner part 27, as clearly shownin Fig. 1-, and the inner wall is located preferably a little outside ofthe line of zero pressure z2, which line has been heretofore explained,that is, a little farther from the axis of rotation than is said line;so that said chamber lO'shall remain full of liquid when revolving atthe designed velocity; and the designed velocity of the machine may bemade such that the line of zero pres sure 2-2 will coincide with theaxis of rotation of the machine, or may even be such that said zero linewill not exist, and there will be a slight pressure at the said axis. Tofacilitate freeing the apparatus from air, a pet cock 19 is attached tothe top of chamber 10. 13 is a brush carried by, and rotating with, theplow 16. 26 is a pipe to convey any liquid which may pass into the drier25 into a stationary circular trough are for use when washing the filter15, as

will be described hereinafter. The position of the line of atmosphericpressure is determined by the valve 38, which is preferably a balancedvalve, controlled by the diaphragm 41, which covers the 'cup or chamber42, and is connected with the outer end of chamber 10 by the pipe 5. Thevalve stem 40 passes through a second diaphragm 39, covering a suitableho'e in the top plate of chamber 10, and is connected by adjusting nutswith the adjusting spring 7. The spring 7' serves to counteract theatmospheric pressure on diaphragm 39 when themachine 'is in motion, andcontrol the motion of the diaphragm 41 and valve 38. A piston andstufling box could be used in place of diaphragms 39 and 41, but weprjefer the diaphragms, to avoid friction and leakage. trolled by supplyvalve 47, by which the amount of material delivered to funnel 6 may beregulated.

The operation is as follows: Suppose the apparatus empty and at rest;and that themixed liquid and heavier particles are run into said pipe 1from valve 47, valve 38 being held closed by pressing onthe top .of stem40, and pet cook 19 being open. The materials will pass down stem 1 outthrough pipes 11 into traps 9, and will fill chamber 10 and connectedmaterials, the lighter hquid filtering through the filter 15 into thepart of chamber 10 nearer the axis ofthe machine. Air will be expelledfrom the apparatus through the pet cock 19. When the machine is full,and all air expelled, thepet cook 19 is closed, the valve 38 is allowedto open, liquid fiows down into and fills the discharge pipe 28 and trap29, and flows into trough 34, and the machine is then started revolvingand gradually attains the desired constant speed. As the speed increasesto its limit, the liquid surface tends to take a vertical position inthe annulus outlet 18; the

suction induced by the centrifugal force of the liquid in pipe 28 causesless than atmospheric pressure in chamber 10; the atmospheric pressureon diaphragm 39 overcomes the. tension of spring 7 and closes 'valve 38until a balance is produced with the "spring pressure on said diaphragmder slde of said diaphragm 41 is dependent on the position of the lineof liquid, or line of atmospheric pressure, since the liquid -spacebeneath said diaphragm 41 is in com- The supply of .mixture is con-'parts with said 41.- The liquid pressure on the unmunication by pipe 5with the liquid in the outer part of said separating chamber 10 and saidannulus 12. Therefore as the atmospheric line tends to move radialloutward, the pressure in 41 falls and V8. ve 38 closes, and should ittend to move radially inward, the valve opens; thus valve 38 'controlsthe position of the line of atmospheric pressure irrespective of theamount of the supplyof materials from valve 47. It. will,

also be evident that should the filter 15 clog, and its resistance tothe flow of fluid increase, the atmospheric line will move radiallyinward in the effort to overcome the increased resistance of the filter;this will cause the valve 38 to'open until the suction induced by thecentrifugal force of the liquid in pipe 28 compensates for the increasedresistance of the filter. The heavier materials separate from the liquidin the outer end of the chamber 10, and concentrate on the walls nearand in the annulus 12. The fine particles are caught and coagulate onthe filter 15, and are brushed off by the brush 13, and pass by thecentrifugal force to saidannulus 12. The materials concentrated at theannulus 12 are plowed upwardly and inwardly along the casing 14', andare deposited on the filtering surface 23 of the drier 25. Any liquiddrained off through filter 23 passes by the pipe 26 to the trough 34.The dried material remaining on 25 is lifted over the edge by the low24, and is discharged into the revolving rum 37, from which it may beremoved in any suitable manner, as by employing a station ary scraper64. The plow 24' is placed in advance of plow 16, so that materialdeposited on filter23 by plow 16 remains drying thereon until removed bythe next succeeding plow 24. One or more sets of plows 16 and 24 may beused. We prefer to use two sets diametrically opposite each other. Thebrush 13 is extended along'the arm connecting it with the plow 16,as wefind that gummy materials will adhere and build up on the inclinedsurface of chamber 10, and the centrifugal force alone may beinsuflicient to dislodge them.

We do not confine ourselves to the partlcular valve and operatingdevices for. the same shown in Fig. 1, but consider any form of valveand operating devices which govern the position of the atmospheric lineby controlling the fiow through the liquid discharge pipe as within thescope of our invention.

Fig. 5 shows another form of our invention arranged to lift the materialto be separated from below by the atmospheric ressure and vacuum inducedby the centri ugal force. The separating chamber 10, caslng 14, plows 16and 24, dr'iers 25, pipe 26, arms 17, filters15", brushes :13, andnumerous other parts are substantially the same in construction andoperation with corresponding parts of Fig. 1, and no further descriptionof such parts is necessary, except to note that said filters 15 andbrushes 13*- are preferably arranged horizontally, and the hollow axisor pipe 1 is now closed at the top and open at the bottom, and worksthrough a stuffing box in the bearing 4. The orifice for the inlet ofthe mixed material is now controlled by the valve 50, which preferablyopens downwardly, and said orifice receives the mixed materials from avessel 53, into which vessel said materials are delivered by a pipe andcont-rolled by a valve 59. Said valve 50 is connected with a lever 55fulcrumed at 56, and connected at its outer end to a float 58. In theform of our apparatus shown on Fig. 5, we do not use the dia hragmcontrolled valve 38 shownon Fig. l, ut regulate the line of atmosphericpressure by the outlet conduit 28 and trap 22 opened to atmosphere at 30on the line of atmospheric pressure, and the discharge pipe 31, whichdelivers the discharged liquid into the trough 34. The operation of thismachine is as follows: The machine being empty, and at rest, liquid isallowed to run into vessel 53 until the inlet and valve 50 are covered;the float 58 is then pushed down in any convenient manner, closing valve50, and the machine is filled with water through the annular opening 18,by a hose or in any other convenient manner, air being allowed to escapethrough the pet cook 19. When the machine is full, pet cock is closed,and the machine started revolving. When the proper speed is attained thefloat 58 is released, and a proper supply of the material to beseparated is admited through valve 59. The liquid rises in the stem 1,passes through openings 11 into chamber 10, and the operation is then asdescribed for Fig. 1, except that the posit-ion of the atmospheric lineis now determined by the position of the trap 22, opened to atmosphereat 30. In this form of apparatus the surface of the liquid in theannulus 18 will be nearer the axis than the atmospheric line, to givesuflicient centrifugal force to overcome the resistance of the filter.

Both forms of the apparatus shown on Figs. 1 and 5 may be used withoutthe filter screens, when thecomplete clarification of the liquid is notimportant. In such cases perforated partitions may be substituted forthe screens to prevent direct flow between the inlet and outletorifices; also radial partitions 60, Fig. 5, may be used to impartangular velocity to the entering liquid. The form shown in Fig. 1 mayalso be used with inlet below, the pipes 11 acting as centrifugal pumps,and the valve 50 being added for priming, or the liquid may beintroduced from below under pressure. The form of machine shown in Fig.1 may be used with inlet either above or below, and with the trappedconduit 28, trap 22, and discharge pipe 31, as shown on Fig. 5, insteadof the diaphragm-regulated valve 38, and this arrangement we prefer incases where the filters 15 are not used.

An arrangement without filters and taking supply from above, is shown inFig. 6. In Fig.6, for convenience of construction, we show the trap 22placed below the separating vessel. The air inlet 67 to trap 22 iscontinued by pipe 67 to a point above trap 9 and pipe 11, and also abovethe outlet end of the liquid discharge pipe 31. The normal atmosphericline in this form of the machine is at a-a. The machine having beenprimed through pipe 1, and started up the atmospheric line is maintainedin position, by the outlet 30 of pipe 31 from trap 22 as described forFig. 5. In this form of the machine the only valve required is that onpipe 47, and in this form of the machine, as in all others embodying ourinvention, the reduced pressure in chamber 10 prevents the lighterliquid from discharging with the heavier concentrates. In Fig. 6, wealso show the drier 25 without filter. The materials are delivered onthe smooth surface of the drier 25, which is placed at such an anglethat the centrifugal force and gravity will not cause the concentratedmaterial to slide on the surface of 25. Any liquid draining from thedrying materials runs back by gravity and centrifugal force into theannulus 18. The shape of the chamber 10 in Fig. 6 is such as will enablethe machine to free itself of air without the said pet cock 19.

The filter may in time become clogged and require washing. This may beaccomplished with apparatus arranged as in Figs. 1 and 4, by'closingcook 61 on pipe 28, and opening. cook 62 on the drip pipe fromchamber-10. Wash water is then let in through cook 63, and the machineis rapidly revolved. The wash water fills the inner part of chamber 10,is forced outwardly through filter 15, or in the direction the reverseof that of the usual flow, cleaning the filter, and discharging throughcock 62 and pipe 25 into trough 34. 1

Referring to Fig. 7, the lighter liquids discharge from chamber 10 bypipe 81, the end of which is provided with a valve seat and controlledby valve 84; said valve 84 being in turn controlled by a. float 83 onvalve stem 85. Said float 83is located in a trap 80 which is connectedwith atmosphere by pipe 82. Therefore, when the machine is running atits proper speed the surface of the liquid in said trap 80 stands on asubstantially vertical wall at the atmospheric line aa. Should theatmospheric line move outward, the surface of the liquid in said trap 80will also move outward and said float 83 will close said valve 84, and

' should the atmospheric line move inward the surface of the liquid insaid trap 80 will move inwardly andsaid float will open said 'valve 84.Thus the float will control the position of the atmospheric line underall circumstances and variations of'supply; this modification being inall essential respects the equivalent of the machine shown in Fig. 1.

Now having described our improvements, We claim as our invention 1. In acentrifugal. machine, a rotating vessel having a circumferential trappedoutlet concentric with the axis of revolution.

2. In a centrifugal separator, a rotating separating vessel having anannular trapped outlet passage extending nearer the axis of rotationthan the extremity of said vessel.

3. The combination in a centrifugal separator of a separating vesselhaving an annular trapped outlet concentric with the axis of rotationfor the heavy concentrated materials extending from said vessel tonearer the axis of rotationthan the extremity of said vessel, and meansfor removing the concentrated materials from said outlet.

'4. The combination in a centrifugal separator of a separating vesselhaving an annular trapped outlet extended from said vesselto a point ofdischarge nearer the axis of rotation than is the extremity of saidvessel and means for removing the concentrates from said outlet.

5. The combination in a centrifugal separator of a separating vessel, anannular trapped outlet for the discharge of heavy cencentrated materialsextending from said.

vessel to a point nearer'the axis of rotation than is the extremity ofsaid vessel, and a discharge conduit-for the liquid separate from saidoutlet for the heavier materials.

'6. In a centrifugal machine an annular outlet therefrom, concentricwith the axis of rotation for the discharge of the heavier separatedmaterials, and means adapted to produce an overbalancing atmosphericpressure opposed to the egress of the lighter liquid from said outlet. s

7. In. a centrifugal machine a revolving separating vessel provided withan annular outlet concentric with the axis of rotation for the dischargeof the heavier concentrated.

materials, and means adapted to produce unbalanced atmospheric pressureto prevent the efilux of the lighter liquid from said annular outlet. a

8. In a centrifugal inachine, the combination of a separating vesselprovidedwith an outlet for the heavier concentrated materials and with aseparate conduit for the discharge of the lighter liquid, and a valvecontrolling said conduit and adapted to maintain lower than atmosphericpressure in a part of said vessel.

9. In a centrifugal machine, the combinationof a separating vesselprovided with an outlet for the heavier concentrates and a separateoutlet for the lighter liquids, and a valve in said last named outletadapted to control the position of the liquid in said vessel. 1

10. In a centrifugal machine the combination. of a separating vessel, afilter therein, and means to control the difference of pressure on thetwo sides of the filter according to the variation of resistance to flowthrough the filter. I

11. In a centrifugal machine a separating vessel, a filter therein, anoutlet conduit for the filtered liquid and. a valve in said conduit tocontrol the difference of pressure on the two sides of the filteraccording to the variation of resistance to flow through the filter.

12. The combination in a centrifugal machine of' a separating vesselcontaining less than atmospheric pressure in a part thereof, and meansfor removing concentrates rotating with said vessel, but at a differentangular-velocityfrom that ,of said vesselfandadapted to move the heavymaterials to a point nearer the axis of rotation than is the line ofatmospheric pressure.

13. The combination in a centrifugal machine of a separating vesselcontaining less than atmospheric pressure in a part thereof, a dischargeconduit for liquid from said vessel, an external annular outlet separatefrom vessel.

16. The combination in a centrifugal machine of a separating vessel anda diaphragm-operated valve controlling the discharge of liquid from saidvessel.

17.. In a centrifugal separator, the combination of a separting vesselprovided with an outlet for the heavier concentrates and a separateoutlet'for the lighter liquid, a valve in said last named outlet adaptedto control the position of-the liquid in said vessel, and

means for operating said valve according to the position of theliquid.

- 18. The combination in a centrifugal separator of a separating vesselcontaining less than atmospheric pressure in a part thereof, an outletfor the heavy concentrated materials, and a trapped inlet for the mixedmaterials opened to atmospheric pressure at substantially the line ofatmospheric pressure.

19. The combination in a centrifugal separator of a separating vesselcontaining less than atmospheric pressure in a part thereof,

an outlet for the heavy concentrated ma-' ing vessel containing lessthan atmospheric pressure in a part thereof, and a filter therein soplaced that the flow of liquid through said nlter is opposed indirection to the centrifugal force.

22. In a centrifugal separator,a separating vessel and a filter soplaced that there will be less than atmospheric pressure on both sidesof said filter.

23. In a centrifugal machine, a filter so placed that the direction ofthe flow through said filter is opposed to the direction of thecentrifugal force, and a brush acting on said filter.

2 1. In a centrifugal machine a filter so placed that the direction ofthe flow through said filter is opposed to the direction of thecentrifugal force, and a brush acting on said filter and means torevolve said brush.

25. In a centrifugal separator, a filter so placed that the direction offlow through said filter is opposed to the direction of the centrifugalforce, and a plurality of brushes acting on said filter.

26. In a centrifugal separator, a filter so placed that thedireetion offlow through said filter is opposed to the direction of the centrifugalforce,.brushes acting to clean said filter and means to control thedifference of pressure on both sides of said filter according to thevariation of resistance to flow through said filter.

27 The combination'in a centrifugal separator of a separating vessel,having an annular outlet for the heavy concentrated materials extendingto nearer the axis of rotation than the extremity of said vessel, and afilter in said vessel so placed that the flow of liquid through saidfilter is opposed in direction tothe centrifugal force.

28. The combination in a centrifugal separator of a separating vessel,having an annular outlet for the heavy concentrated materials extendingto nearer the axis of rotation than the extremity of said vessel,

a filter in said vessel so placed that the flow of liquid through saidfilter is opposed in direction to the centrifugal force, and brushes toclean said filter.

29. The combination in a centrifugal separator of a separating vessel,having an annular out-let for the heavy concentrated materials extendingto nearer the axis of rotation than is the extremity of said vessel,means in said outlet for the extraction of the heavy concentratedmaterials, and a filter in said vessel so placed that the flow of liquidthrough said filter is opposed in direction to the centrifugal force.

30. The combination in a centrifugal separator of a separating vessel,having an annular outlet for the heavy concentrated ma- .terialsextending to nearer the axis of rotation than the extremity of saidvessel, means in said outletfor the extraction of the heavy concentratedmaterials, and a filter in said vessel so placed that the flow of liquidthrough said filter is opposed in direction to the centrifugal force,and brushes to clean said filter.

31. The combination in a centrifugal separator, of an annular rotaryseparating vessel provided with separate outlets for the discharge ofheavier concentrates and lighter liquid, means to produce lower thanatmospheric pressure in a -part of said vessel, and means for removingthe concentrates from said vessel.

32. The combination in a centrifugal separator, of an annular rotaryseparating vessel provided with separate outlets for the dis:

1 charge of heavier concentrates and lighter liquid, means to producelower than atmospheric pressure in a part of said vessel, a filter inthe area of said lower pressure, and means for removing the concentratesfrom said vessel.

33. The combination in a centrifugal sep- 1 5 arator, of a rotaryseparating vessel provided with separate outlets for discharge ofheavier concentrates and lighter. liquid, means to produce lower thanatmospheric pressure in a part of said vessel, a filter in the area ofsaid lower pressure, and means for removing said concentrates from saidvessel. I

Signed at New York city in the county of New York and State of New York,this 29th day of July A. D. 1911.

HARALD nn RAASLOFF. THOMAS E. BROWN.

Witnesses:

G. W. Horxms, WALTER ALnLERs.

